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Technological Issues an Informal learning case • I plan to ride in Europe for vacation, on a motorcycle. – I need to learn more about travelling on motorcycle across Europe • Rider’s apparel: boots, jackets, pants, gloves, armor, etc. • Motorcycle accessories: luggages, side cases, topcases, tank bags, GPS, etc. • Riding issues, skills, etc. – According to my social networks, I know there is a teacher at Telecom Bretagne who used to ride across Europepage 3 Semantic Web in Action

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Who is teaching at Telecom Bretagne and riding a motorcycle across Europe?page 4 Semantic Web in Action

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Semantic Web¢ The Semantic Web is a web of data. • There is lots of data we all use every day, and it is not part of the web. • I can see my bank statements on the web, and my photographs, and I can see my appointments in a calendar. • But can I see my photos in a calendar to see what I was doing when I took them? • Can I see bank statement lines in a calendar?¢ Why not? • Because we dont have a web of data. • Because data is controlled by applications, and each application keeps it to itself. Semantic Web in Action

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Semantic Web ¢ The Semantic Web is about two things. - It is about common formats for integration and combination of data drawn from diverse sources - On the contrary, the original Web is mainly concentrated on the interchange of documents. - It is also about language for recording how the data relates to real world objects (meaning).page 11 Semantic Web in Action

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Semantic Web ¢ The Semantic Web • That allows a person, or a machine, to start off in one database, and then move through an unending set of databases which are connected not by wires but by being about the same thing. • Provides a common framework that allows data to be shared and reused across application, enterprise, and community boundariespage 12 Semantic Web in Action

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The Semantic Web ¢ The Semantic Web is about two things. - It is about common formats for integration and combination of data drawn from diverse sources - On the contrary, the original Web is mainly concentrated on the interchange of documents. - It is also about language for recording how the data relates to real world objects (meaning).page 13 Semantic Web in Action

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The Semantic Web ¢ That allows a person, or a machine, to start off in one database, and then move through an unending set of databases which are connected not by wires but by being about the same thing. ¢ Provides a common framework that allows data to be shared and reused across application, enterprise, and community boundaries ¢ The Semantic Web will enable machines to COMPREHEND semantic documents and data, not human speech and writings.page 14 Semantic Web in Action

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Linked Data ¢ Linked Data • Is a term used to describe a method of exposing, sharing, and connecting data on the Web via dereferenceable URIs. ¢ Principles (Tim Berners-Lee) • The Semantic Web isnt just about putting data on the web. It is about making links, so that a person or machine can explore the web of data. With linked data, when you have some of it, you can find other, related, data. • Like the web of hypertext, the web of data is constructed with documents on the web. However, unlike the web of hypertext, where links are relationships anchors in hypertext documents written in HTML, for data they links between arbitrary things described by RDF. The URIs identify any kind of object or concept. Source : Wikipedia, Tim Berners Leepage 23 Semantic Web in Action

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Linked Data ¢ Tim Berners-Lee outlined four principles of Linked Data in his Design Issues: Linked Data note, paraphrased along the following lines: • Use URIs to identify things that you expose to the Web as resources. • Use HTTP URIs so that people can locate and look up (dereference) these things. • Provide useful information about the resource when its URI is dereferenced. • Include links to other, related URIs in the exposed data as a means of improving information discovery on the Web.page 24 Semantic Web in Action

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Linked Data ¢ Linking Open Data Community Project • The goal of the W3C Semantic Web Education and Outreach groups Linking Open Data community project is to extend the Web with a data commons by publishing various open datasets as RDF on the Web and by setting RDF links between data items from different data sources. As of October 2007, datasets consist of over two billion RDF triples, which are interlinked by over two million RDF links. (Wikipedia)page 25 Semantic Web in Action

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Linked Data ¢ DBpedia • Is a community effort to extract structured information from Wikipedia and to make this information available on the Web. DBpedia allows you to ask sophisticated queries against Wikipedia, and to link other data sets on the Web to Wikipedia data. ¢ Resources • http://wiki.dbpedia.org/About • http://blog.dbpedia.org/ • http://www4.wiwiss.fu-berlin.de/dbpedia/dev/ontology.htmpage 28 Semantic Web in Action

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Linked Data ¢ GovTrack.us • The SPARQL engines base URL is http://www.rdfabout.com/sparql , following (or trying to follow) the SPARQL Protocol spec. • The SPARQL engine is Ryan Leverings engine for SESAME, plus my SemWeb library for C#. • The data store is persisted in MySQL. Responses are limited to 1000 rows in the hopes that having this public wont break anything.page 37 Semantic Web in Action

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Linked Data ¢ Revyu.com • Revyu.com is a web site where you can review and rate things. Unlike many other reviewing sites on the web, Revyu.com lets you review and rate absolutely anything you can name • Web access: http://revyu.com/ • SPARQL Endpoint http://revyu.com/sparql/page 38 Semantic Web in Action

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SPARQL: SPARQL Protocol and RDF Query Language ¢ SPARQL • pronounced "sparkle" [1]) is an RDF query language; its name is a recursive acronym that stands for SPARQL Protocol and RDF Query Language. It is standardized by the RDF Data Access Working Group (DAWG) of the World Wide Web Consortium, and is considered a component of the semantic web. • Initially released as a Candidate Recommendation in April 2006, but returned to Working Draft status in October 2006, due to two open issues. [2] In June 2007, SPARQL advanced to Candidate Recommendation once again. [3] On 12th November 2007 the status of SPARQL changed into Proposed Recommendation. [4] On 15th January 2008, SPARQL became an official W3C Recommendation. [5]page 39 Semantic Web in Action

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SPARQL: SPARQL Protocol and RDF Query Language ¢ « Construct » • The CONSTRUCT query form returns a single RDF graph specified by a graph template. - The result is an RDF graph formed by taking each query solution in the solution sequence, substituting for the variables in the graph template, and combining the triples into a single RDF graph by set union. • Useful for aggregating data from multiple sources and merging it into a local store (from Ingenta)page 52 Semantic Web in Action

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SPARQL: SPARQL Protocol and RDF Query Language ¢ ASK • Returns a true/false value: test whether or not a query pattern has a solution. • No information is returned about the possible query solutions, just whether or not a solution exists • Is there data that looks like this? Do you have any information about that? (from Ingenta) ¢ PREFIX foaf: <http://xmlns.com/foaf/0.1/> ASK WHERE { ?person a foaf:Person; foaf:mbox <mailto:ab@telecom-bretagne>. }page 54 Semantic Web in Action

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SPARQL: SPARQL Protocol and RDF Query Language ¢ DESCRIBE • The DESCRIBE form returns a single result RDF graph containing RDF data about resources. • CONSTRUCT but with less control - Tell me about this or things that look like this … but you decide what’s relevant (from Ingenta) ¢ PREFIX foaf: <http://xmlns.com/foaf/0.1/> DESCRIBE ?friend WHERE { ?person foaf:mbox “mailto:ab@telecom-bretagne”; foaf:knows ?friend.}page 55 Semantic Web in Action